Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Northbrook experiences four distinct seasons with an average annual temperature of 50°F (10°C). Winters average 24°F in January while summers reach 73°F in July. The area gets 260 sunny days per year, above the national average. Annual precipitation totals 39.5 inches. The area receives 33.6 inches of snow annually, a moderate snowfall amount. Air quality is rated Good with a median AQI of 43. The city sits at an elevation of 669 feet.
Temperature
24°F Jan (-4°C)73°F Jul (23°C)
Annual Average
49.6°F
8% below US avg
January Average
24°F (-4°C)
July Average
73°F (23°C)
Sunny Days
260 days/yr
Geography
Elevation
669 ft (204 m)
Area
13.3 sq mi (34.3 km²)
Population Density
2,614/sq mi
Coordinates
42.1287°N, 87.8352°W
Timezone
America/Chicago
County
Lake County County
Nearest Airport
Chicago O'Hare International (ORD) 11 miles away
Precipitation & Snow
Annual Rainfall39.5"
4% above US avg
Snowfall33.6"
Wettest Month (Aug)4.17"
Driest Month (Feb)1.42"
Air Quality
AQI Median
43.0
Rating
Good
Natural Hazard Risk
Overall Risk
Relatively High
Risk Score
96.0 / 100
Social Vulnerability
14.1 / 100
Community Resilience
78.1 / 100
Hazard Breakdown
Tornado
Very High
Hurricane
Very Low
Earthquake
Relatively Low
Wildfire
Very Low
Flood
Relatively High
Hail
Relatively Moderate
Strong Wind
Very High
Heat Wave
Relatively Moderate
Winter Weather
Relatively Moderate
Lightning
Relatively High
Ice Storm
Relatively Moderate
Drought
Relatively Low
Cold Wave
Very High
Landslide
Very Low
Coastal Flood
Very Low
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
8 earthquakes (M2.5+) recorded within 150 km since 1990.
Strongest on record: M4.2.
Jun 28, 2004
12 km NW of Dayton, Illinois
M4.2
115 km
10 km
Feb 10, 2010
2 km NW of Lily Lake, Illinois
M3.8
58 km
10 km
Sep 2, 1999
8 km W of Amboy, Illinois
M3.5
140 km
5 km
Nov 4, 2013
1 km SSW of Lyons, Illinois
M3.2
37 km
1 km
Jul 15, 2024
2 km WNW of Somonauk, Illinois
M3.1
90 km
10 km
Mar 25, 2015
3 km WNW of Lake in the Hills, Illinois
M2.9
44 km
6 km
Jun 10, 2013
4 km NNE of Virgil, Illinois
M2.6
58 km
5 km
Mar 15, 2025
6 km W of Dwight, Illinois
M2.6
128 km
5 km
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.
Tornado History
496 tornadoes (EF0+) recorded within 100 km since 1950.
Strongest on record: EF5. Total: 105 fatalities, 2,221 injuries.
Date
Rating
Distance
Path
Fatalities
Aug 28, 1990
EF5
66 km
16.4 mi
29
Jun 29, 1979
EF4
75 km
5.4 mi
0
Jun 13, 1976
EF4
53 km
3.3 mi
2
Sep 28, 1972
EF4
17 km
5.2 mi
0
Apr 21, 1967
EF4
51 km
15.0 mi
33
Apr 21, 1967
EF4
36 km
8.8 mi
1
Apr 21, 1967
EF4
90 km
25.5 mi
24
Apr 11, 1965
EF4
46 km
9.1 mi
6
Jun 20, 2021
EF3
52 km
17.6 mi
0
Jan 7, 2008
EF3
62 km
10.8 mi
0
Jan 7, 2008
EF3
87 km
13.2 mi
0
Mar 27, 1991
EF3
65 km
15.0 mi
0
Apr 27, 1984
EF3
76 km
9.0 mi
1
Mar 12, 1976
EF3
86 km
12.6 mi
0
Mar 12, 1976
EF3
70 km
22.6 mi
0
Oct 24, 1967
EF3
82 km
0.1 mi
0
Nov 12, 1965
EF3
71 km
4.1 mi
0
Jul 19, 1963
EF3
61 km
10.6 mi
0
Apr 23, 1961
EF3
92 km
51.7 mi
0
Jul 15, 2024
EF2
94 km
34.6 mi
0
Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).
Tsunami History
1 tsunami recorded within 500 km.
Highest wave on record: 3.0 m (10 ft).
Year
Location
Cause
Max Wave
Deaths
Distance
1954
MICHIGAN CITY, IN (LAKE MICHIGAN)
Avalanche
3.0 m
7
92 km
Source: NOAA/NCEI Historical Tsunami Database.
Wildfire History
12 wildfires (100+ acres) recorded within 100 km.
Largest: UNNAMED (1,741 acres, 2019).
Year
Name
Acres Burned
Distance
2019
UNNAMED
1,741
88 km
2019
UNNAMED
1,664
87 km
2021
NORTHEAST PRAIRIE UNIT 3
978
86 km
2024
NORTHEAST PRAIRIE 3 RX
938
85 km
1986
OGDEN DUNS
863
77 km
2021
UNNAMED
738
84 km
2021
MIDDLE GRANT CREEK
700
88 km
2019
UNNAMED
698
84 km
2024
IBSP SOUTH F1 RX
690
31 km
2021
21-INDU TOLLESTON DUNES EAST
594
78 km
2017
UNNAMED
549
89 km
2017
17 INDU COWLES DUNES
522
81 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
24°F (-4°C)
1.7 in
Coldest
February
27°F (-3°C)
1.4 in
Driest
March
37°F (3°C)
2.5 in
April
48°F (9°C)
3.6 in
May
59°F (15°C)
3.5 in
June
69°F (21°C)
3.8 in
July
73°F (23°C)
3.7 in
Warmest
August
72°F (22°C)
4.2 in
Wettest
September
64°F (18°C)
3.5 in
October
53°F (11°C)
2.5 in
November
40°F (4°C)
2.8 in
December
27°F (-3°C)
2.3 in
Northbrook has a seasonal temperature swing of 49°F / from 24°F in January to 73°F in July. Total annual precipitation is 35.6 inches, with August being the wettest month (4.2") and February the driest (1.4").